Elevator door operator



Patented Oct. 10, 1939 UNITED STATES PATENT OFFICE ELEVATOR DOOR OPERATOR Application May 14, 1937, Serial No. 142,640

1 Claim.

My invention relates to elevator door operators and more particularly to operators for elevator doors having an upper door section and a lower door section vertically and oppositely movable on a pair of guides by a pair of flexible connectors.

The construction and operation of counterbalanced hatchway doors is old and well known in the art but where very wide doors are used,

as in freight elevators, and particularly in garages, considerable difiiculty has been experienced in providing door operators which will effect the raising or lowering of the door sections in a smooth and eificient manner without causing it! them to tilt to one side and wedge or stick on their guides.

One object of the invention is to provide an operator or vertically mounted counterbalanced doors which will raise or lower the door sections without causing any binding of the doors on their guides.

Another object of the invention is to provide for counterbalanced doors, an individual operator which may be mounted approximately between the guides for the doors and in which each element will be sufliciently short to prevent backlash or other lost motion which might impair the efficiency of the door operator.

It is also an object of the invention to provide a door operator which is very simple and inexpensive to construct, install and maintain in operation.

For a better understanding of the invention, reference may be had to the accompanying drawings, in which ,Figure 1 is a top plan View, partly in section, of an elevator door operator embodying my invention, as installed at a landing in an elevator hatchway.

Fig. 2 is a view of the door operator and counterbalanced door illustrated in Fig. 1 as they appear from the interior of the elevator hatchway;

Fig. 3 is a top plan view, partly in section, of a modification of the door operator illustrated in Fig. 4 is a front elevational view of a modified form of the driving means for the door operator illustrated in Fig. 3;

Fig. 5 is a top plan view, partly in section, of

another form of the door operator illustrated in Fig. l; and,

Fig. 6 is a front elevational view of the driving means illustrated in Fig. 5.

Referring more particularly to Figs. 1 and 2 of the drawings, a portion of an elevator car 0 is shown in Fig. 1 as disposed opposite a hatchway floor landing II represented by the hatchway walls l2.

The hatchway opening II is providedwith a hatchway door l8 comprising an upper door sec- 5 tion l9 and a lower door section 20 mounted upon a pair of vertical guides 2| and 22 by means of a plurality of guide clips 23. The door is of the counterbalanced type in which the door sections move vertically and oppositely upon the 10' guides when the door is being opened or closed. The means for connecting the door sections for their counterbalanced operation comprises a pair of flexible chain or cable connectors 25 and 26, the inner ends of which are fastened to clevis ll 2'! and a clevis 28 disposed on clips 29 and 30 attached to the lower outside edges of the upper door section. The center portion of the cable 25 passes outwardly over a first balancing sheave 3| to where its outer end is attached by means of 20 a clevis 32 to the outer end of a bar 33 secured to the upper portion of the lower door section 28, as by a plurality of bolts 36. The middle portion of the cable 26 passes outwardly over a second balancing sheave 34 to where its outer end 25 is attached by a clevis 35 to the right-hand end of the bar 33.

With this construction, it will be seen that the doors are suspended on the sheaves by the flexible connectors-and that the weight of the upper 30 door section tends to counterbalance the weight of the lower door section. Hence, by rotating the sheaves, the connectors may be caused to move the door sections in opposite directions to either open or close the door. 35

In providing operators for very large doors, where the doors are say ten to fifteen or twenty feet wide, the doors have a tendency to stick on their guides or the door operating mechanism develops too much lost motion or backlash for 40 smooth and eiiicient operation. In order to overcome these difiiculties, I have provided for rotating the sheaves by a means comprising a motor 31 mounted approximately midway between the door guides and a suitable operating mecha- 45,

nism 38 for connecting the motor to the sheaves for operating the doors in accordance with the operation of the motor. As illustrated in Fig. l, the motor 31 may be mounted in an aperture or hole 39 in the hatchway wall l2 at a point ap- 50 proximately central of the door guides by means of a tube like projection of the motor end bell 40 which may be secured to the hatchway wall l2 by a plurality of suitable bolts 4|. In the operator shown, the motor is disposed on the wall of the corridor at that landing, but inasmuch as this door operator is provided mainly for garage and freight elevators, the position of the motor in the corridor will not be objectionable and the space which is usually required in the hatchway for housing the motors of the door operators will not be required. Hence, there will be a saving in construction of the hatchways where door operators of the present character are employed.

The operating mechanism 38 comprises a first gear wheel 43 mounted upon a stub shaft 44 and a second gear wheel 45 mounted upon a stub shaft 46. The shafts 44 and 46 are mounted by suitable bases 41 upon a cross frame 48 or portion of the hatchway wall. The supporting bases are placed close together so that the gear wheels 43 and 45 mesh with each other to cause them to rotate in opposite directions when either one of them is rotated.

The motor 31 is provided with a pinion 50 that is disposed to engage the gear wheel 43 so that rotation of the motor in the direction of the arrow will cause the gear wheel 43 to rotate in the direction of the arrow 52 and the gear wheel 46 to rotate in the direction of the arrow 53. A driving pulley 54 is secured to the gear wheel 43 on the shaft 44. A belt 55 is disposed upon the pulley 54 in position to extend to and around a driven pulley 56 mounted on a shaft 51 for supporting the sheave 3|. The shaft 51 is supported by a bracket 53 on the hatchway wall at the landing Inasmuch as the pulley 56 and the sheave 3| are fixed on the shaft 51, rotation of the pulley 54 by its gear wheel 43 will cause the pulley 56 and the shaft 3| to rotate for operating the flexible connector 25 when the door is to be raised or lowered.

A driving pulley 66 is secured to the gear wheel 45. A belt 6| extends from the pulley 66 to pass over a drive pulley 62 attached to a shaft 63 on which the sheave 34 is fixed. A bracket 64 supports the shaft. Hence rotation of the gear wheel 45 causes the belt 6| to rotate the sheave 34.

By the foregoing construction, it will be seen that if the motor is rotated in the direction of the arrow 5| (Fig. 2) the pinion 50 will rotate the gear wheel 43 in the direction of the arrow 52. This will rotate the pulley 54 in the direction of the arrow 52, and the belt 55, the pulley 56 and the sheave 3| in the direction of the arrow 66. At the same time, the rotation of the gear wheel 43 in the direction of the arrow 52 will cause the gear wheel 45 and its attached pulley 60 to rotate in the direction of the arrow 53. This causes the belt 6|, the pulley 62 and the sheave 34 to rotate in the direction of the arrow 61. Inasmuch as the sheave 3| is rotating in the direction of the arrow 66 and the sheave 34 in the direction of the arrow 61, the flexible connectors 25 and 26 will be operated to raise the door section L3 and lower the door section 20 so that the hatchway opening H is opened for entrance to the car C.

When it is desired to close the hatchway door, the motor 31 is operated in a direction reverse to that of the arrow 5|, which causes the gear wheels 43 and 45 to be rotated in directions opposite to each other and opposite to the arrows 52 and 53. This, in turn, causes the belts 55 and 6| to eifect the rotation of the sheaves 3| and 34 in directions opposite to the arrows 66 and 61, thereby moving the connectors 25 and 26 to lower the door section |9 and raise the door section 20 to close the hatchway opening Referring to Fig. 3 of the drawings, the driving motor 31 therein illustrated is mounted upon a supporting plate 68 on the outside of the wall l2 of the hatchway. The pinion 50 on the motor 31 is disposed to mesh with the gear wheel 43 which, in turn, meshes with the gear wheel 45. The gear wheels are disposed on the outside of the wall instead of the inside of the wall as shown in Fig. I, and are supported by a pair of shafts 69 and which extend through the wall and have mounted on their inner ends a pair of pulleys 54 and 66. The shafts 69 and 10 are supported in bushings 1| and 12. The drive pulleys 54 and 60 operate the belts 55 and 6| in the same manner as in Fig. 1, and have the additional advantage of requiring a very small space in the case above the door.

Referring now to Fig. 4, the modified form of drive illustrated therein is the same as that of Fig. 3, except that the motor 31 is provided with a pulley or sprocket 13 for driving a chain 14 which extends over a sprocket wheel and under and around a sprocket wheel 16. The sprocket Wheel 15 is a substitute for the gear wheel 43 and the sprocket wheel 16 is a substitute for the gear wheel 45, so that the motor 31 may operate the pulleys 54 and 66 by means of a chain drive to effect the same operation of the sheaves 3! and 34, as is provided by the apparatus shown in Fig. 1.

Referring now to Figs. 5 and 6 in this modified form of the door operator the motor 31 is provided with a pulley or sprocket 56b which operates a belt or chain 86 to rotate a sprocket wheel 8|. The sprocket wheel 5% and the sprocket wheel 8| are mounted on the outside of the hatchway wall, the wheel 8| being disposed on the end of a shaft 1|a which passes through the wall l2 and has on its inner end a pair of driving pulleys 54a and 60a. The wheel 8| and the pulleys 54a and 60a are fixed on the shaft lie, so that operation of the sprocket 5% causes the driving pulleys to rotate in the same direction. The pulley 60a is provided with a belt 6| a which is disposed to engage that pulley and pass over an idler wheel 11 to the driving pulley 62. The pulley 54a is provided with a belt 55 which passes around the driving pulley 56. With this construction, the operation of the motor 3? causes the driving pulleys 56 and 62 to operate the door sections in the same manner as the apparatus iilustratedin Fig. 1.

By either one of the foregoing constructions, it will be seen that I have provided a simple and inexpensive elevator door operator, that it may be located in a conveniently accessible position approximately midway between the guides for the hatchway door, that the connecting elements between the motors and the sheaves operated thereby are approximately half the length they would be if the door operator were located at one side or the other of the doors and that consequently there is little room for backlash or lost motion in the door operating apparatus. Furthermore, inasmuch as the power is applied equally and directly to each driving sheave, the door sections will be raised or lowered without undue tilting at either end.

Although I have illustrated and described several specific embodiments of my invention, it is to be understood that other modifications thereof and changes therein may be made without departing from its spirit and scope.

I claim as my invention:

In an operator for a door having an upper section and a lower section vertically and oppositely movable on a pair of guides by a pair of flexible connectors to close an opening in a hatchway wall, a sheave mounted adjacent the upper portion of one of the guides for operating one of the connectors, a second sheave mounted adjacent the upper portion of the other guide for operating the other connector, a motor mounted on the outside face of the hatchway wall above the doorway and at approximately the center thereof with the shaft of the motor extending inwardly through the Wall, a pinion mounted on the end of the motor shaft inside the wall, a first gear wheel mounted in mesh with the pinion, a second gear wheel mounted in mesh with said first gear wheel, a first wheel mounted on the shaft of said first gear wheel, a second wheel mounted on the shaft of said second gear wheel, driving means connecting said first wheel to one of said sheaves, and a driving means connecting said second wheel to the other of said sheaves whereby operation of the motor causes the door to open or to close in accordance with the direction of operation of the motor.

HAROLD V. MCCORMICK. 

